<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>

<body>
  <form action="/abc">
    <select name="fruits" id="">
      <option value="apple">苹果</option>
      <option value="banana">香蕉</option>
      <option value="orange">橘子</option>
    </select>
    <div>
      <input type="submit">
    </div>
  </form>
  <hr>
  <form action="/abc">
    <select name="fruits" id="" multiple>
      <!-- selected默认选中 -->
      <option value="apple" selected>苹果</option>
      <option value="banana">香蕉</option>
      <option value="orange">橘子</option>
    </select>
    <div>
      <input type="submit">
    </div>
  </form>

</body>

</html>